RESUMEN
Although a number of studies suggest that different immune pathways may play a role in the pathogenesis of non-Hodgkin's lymphomas (NHL), the shape of the T-cell compartment has been only superficially explored in these patients. In our study, we analyzed the peripheral T-cell receptor (TCR) repertoire and the distribution of different T-cell subsets - including regulatory T cells (Treg) - in 30 patients with NHL, by combining flow cytometry and spectratyping. We first demonstrated by flow cytometry an increased frequency of expanded T-cell subpopulations expressing the same TCR beta variable (BV) subfamilies in CD8+ cells from NHL patients when compared with healthy controls, beside a higher frequency of Treg. Moreover, NHL patients were characterized by a higher percentage of BVs showing a skewed CDR3 profile both in CD4+ and CD8+ cells when analyzed by spectratyping. Our data suggest that the T-cell branch of the immune system of patients with B-cell NHL is deeply deranged, as witnessed by the increased degree of activation and skewing of their TCR repertoire along with the higher frequency of Treg.
Asunto(s)
Linfoma de Células B/genética , Linfoma de Células B/inmunología , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Médula Ósea/patología , Evolución Clonal , Regiones Determinantes de Complementariedad/genética , Regiones Determinantes de Complementariedad/metabolismo , Femenino , Citometría de Flujo , Humanos , Inmunofenotipificación , Inmunoterapia , Recuento de Linfocitos , Linfoma de Células B/diagnóstico , Linfoma de Células B/terapia , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Receptores de Antígenos de Linfocitos T alfa-beta/metabolismo , Subgrupos de Linfocitos T/efectos de los fármacosRESUMEN
The T-cell receptor (TCR) is the key player within the so called immunological synapse and the analysis of its repertoire offers a picture of both versatility and wideness of the whole immune T-cell compartment. Among the different approaches applied to its study the so-called spectratyping identifies the pattern of the third complementarity determining region (CDR3) length distribution in each one of the beta variable (TRBV) subfamilies encoded by the corresponding genes. This technique consists in a CDR3 fragment analysis through capillary electrophoresis, performed after cell separation, RNA extraction and reverse transcriptase PCR. This review will run through the most relevant studies which have tried to dissect the TCR repertoire usage in patients with different immune-mediated and infective diseases as well as solid or haematologic malignancies.
Asunto(s)
Enfermedades Transmisibles/inmunología , Regiones Determinantes de Complementariedad/inmunología , Genes Codificadores de los Receptores de Linfocitos T , Neoplasias Hematológicas/inmunología , Enfermedades del Sistema Inmune/inmunología , Técnicas Inmunológicas , Receptores de Antígenos de Linfocitos T/inmunología , Linfocitos T/inmunología , Animales , Separación Celular , Enfermedades Transmisibles/genética , Regiones Determinantes de Complementariedad/genética , Electroforesis Capilar , Neoplasias Hematológicas/genética , Humanos , Enfermedades del Sistema Inmune/genética , ARN/genética , ARN/aislamiento & purificación , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Linfocitos T/metabolismoRESUMEN
Patients with myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) with multilineage dysplasia show several immunological abnormalities. In this clinical setting, by combining flow cytometry and CDR3 spectratyping we monitored the kinetic of the T-cell repertoire during Azacitidine treatment, in order to explore its potential ability to reverse the immune derangement typical of these disorders. We firstly demonstrated by flow cytometry an increase in both CD4+ and CD8+ T-cell frequencies after starting treatment. Moreover, when monitored by spectratyping our patients showed significant changes in their T-cell receptor (TCR) CDR3 profiles, which were much more evident in helper T-cells. In fact, the frequency of BV (beta variable) subfamilies showing a skewed CDR3 profile significantly decreased from baseline to the following evaluations in CD4+ T-cells (81% vs. 70%). This pattern was even more pronounced in patients responding to Azacitidine (90% vs. 61%). Our data show that the overall derangement of the T-cell repertoire detectable in patients with MDS and AML with multilineage dysplasia gradually improves during Azacitidine treatment. These findings therefore suggest that Azacitidine could be potentially able, not only to restore the hematopoietic function, but also to reverse the immune derangement typical of these hematologic disorders.